The ability to bond different substrates together to form a bonded article is useful for a variety of different industries. As one example, the semiconductor industry uses material bonding techniques to bond different substrates together during semiconductor fabrication. As another example, the electronics industry uses bonding techniques to bond different substrates together during circuit fabrication. In addition, the medical device industry uses material bonding techniques to bond different materials together during medical device construction.
Direct wafer bonding is one type of bonding technique that is frequently used to bond semiconductor wafer materials together. Direct wafer bonding involves bonding wafer materials together without the aid of a specific bonding agent such as, for example, adhesive, wax, solder, or the like. Direct wafer bonding often involves preparing substrates so that atomic attraction forces can molecularly bond the substrates together when the substrates are brought into close contact. In some examples, the substrates are placed between two heated platens after bringing the substrates in close contact to cause covalent bonds to form between the different substrates.
Direct bonding techniques may be used to form component packages. A component package may house a component such as, e.g., an electrical component. A component package may be useful to protect the component from different environmental conditions such as, e.g., pressure changes, moisture, bodily fluids, or the like. However, because the process of forming a direct bond may involve heating the bond to an elevated temperature, temperature-sensitive components may experience thermal damage when placed in a package that is subsequently sealed using direct bonding techniques. Moreover, because the process of forming a direct bond may involve one or more cycles of heating and cooling, mismatches between coefficients of thermal expansion for different substrates being bonded may cause warping and thermal stress fractures to develop between the different substrates. Warping and thermal stress fractures may weaken the bond between the different substrates and may reduce the hermeticity of a component package formed using direct bonding techniques.